1. Field of the Invention
The present invention relates to a common multimedia interface (MMIF) circuit that allows any signal source, whether it be an analog phone, digital phone, PC, or video device, to be connected through the MMIF circuit to a network such as an intranet.
2. Description of the Related Art
A communication system in an office or site environment may have a variety of signal sources such as analog and digital telephones, PC's, and video sources that all need to be connected to a network, for example an intranet. An intranet is a private network built around internet technology and standards. An example would be a government agency that may have a variety of offices in a number of locations that are all connected by an intranet.
FIG. 1 shows a typical prior art office environment having an analog telephone system in parallel with a digital local area network (LAN) using, for example, Ethernet protocol to which personal computers (PCs) are connected. The disadvantage of this system is that the analog phone system and digital LAN network have separate transmission lines.
FIG. 2 shows a more advanced prior art communication system in which one set of transmission lines is eliminated. Telephones are connected through multimedia PCs to the LAN thus eliminating one set of transmission lines. The disadvantage of having the analog telephones go through the PCs is that this requires adding a telephone interface card to the PC. Secondly, if the PC fails, the phone is unusable. In addition, when the phone is in operation the PC operation is degraded.
FIG. 3 is a schematic drawing of the latest state of the art system that provides long distance telephone calls over the internet. The system connects the telephone to a “box” which performs a long distance call over the internet to another “box” which has a phone connected to it. The disadvantage of this system is the reliability of connections over the internet for a telephone call.
What would be desirable is a communication system in an office environment in which each signal source connects through its own standard interface box to the network such that each signal source may communicate to any other signal source without having to modify any of the signal sources.